The ISS is already a space port and repair facility. Didn't the shuttle dock and perform repairs? Why yes it did! I'd think that extending some beams and lattice work out from the ISS, running some facilities along it would make it the beginnings of a space port.

I'd prefer a dedicated facility though. I'm thinking a cross between the construction yard (not dock) from an early Star Trek movie (can't remember which one), and the hospital station Riply wakes up on in the Aliens movie. A hollow Aliens type structure could well be the centre of space tether, with the counterweight being the stations habitat swinging way out there, creating some gravity like effect.

To make a real useful dock yard, you need to supply it cheaply. It'd be like building a floating dock yard out at sea. Why would you do that? So that means we'd need the space elevator up and running.

We could use the tethers to swing ships out of Earths orbit too couldn't we? Lift a completed craft to the end of the tether, and let go at just the right moment. Wheeeee!

What about an inflateable space-dock with a rigid, cube endo-skeleton assembled inside it in orbit? Pump out the air, un-zip the door, move your vehicle inside, zip up the door and pump the air back in.

The dock-workers can work in a shirt sleeve environment. Paasengers can transfer without suits or fragile hard docking ports.

Loads of air would be required to presurise a dock. Think of the size of the Shuttle Assembly Building. Wow! The passenger embarkation would be down a "walkway" anyway, so why not just connect a nice carpet lined pressurised walkway to the airlock? Makes no difference to them. The maintenance crew might find it more comfortable in air filled environment, but I'd think that simply being in a dock, they could connect their pressurised suits to the docks environmental systems. This might make their suits much lighter and easier to work in, as their backpacks wouldn't be needed. Just a helmet, shoes, gloves and helmet. There'd be plenty of artificial light too, so no need for head lamps.

That'd work, but it's not quite the same as getting your hands on something is it? Cranes, robot arms, and internal transport could use the gantry rails and such, I'd have thought. A crane structure with personnel platforms on, in addition to a couple of robot arms, could traverse the dock taking tools, equipment, lifting gear, and everything else all at the same time, right to the job site. Nice!

Simple refuelling might not require personnel to go out anyway, a robot arm with a filler hose would likely suffice.

There could be small "coffee break rooms" built in and around the structure too. Somewhere to chill before the next shift. Ha!

Space gloves are very hard to work in. Ask any astronaut with EVA experience. That's why one of NASA's centenial challenges is a lighter, more flexible glove. Any task takes many times longer and much rehearsing.

Air is light. Even at 1 atm a cubic metre of air only masses 1.2 kg. A 20m diameter sphere would require less than 2300kg of air at say one half atm, with 30% oxygen).

You wouldn't service a Shuttle with External Tank and SRB's!. But a CEV, Soyuz, Klipper, CXV or Dragon should fit easily.

If every square metre of the cover weighs 1kg that's another 1250kg.
12 x 14m and 5 x 20m (cross bracing) aluminium poles & couplings, add another 1300kg. 500kg more for a door frame. Add 3000kg for power, pumps and tanks. 1500kg for tools and equipment.

And it even fits on a current LV. Nice job, Cadet. My main question is micrometiorite protection, since the consequences of a hull puncture are obviously rather nasty (since nobody inside is wearing suits).

And it even fits on a current LV. Nice job, Cadet. My main question is micrometiorite protection, since the consequences of a hull puncture are obviously rather nasty (since nobody inside is wearing suits).

Good point, as a WAG I though one kg per square metre was pretty strong, but it only equates to about 0.6 mm of kevlar. Several layers of something like Kevlar/Nomex/Aluminium, adding up to several mm thick, would probably be needed. That would increase the cover weight by 3 to 5 times (maybe 5 tonnes). Still doable, but starting to push it.

Another option is to separately launch tanks of water to pump into the cover and freeze. Should be self sealing. This would also act as a good radiation shield. 12.5 tonnes is needed for a 10 mm thick layer, although multiple layers would be better.

A hull puncture may not be that bad. Such a large volume (4000+ m3) will not depressurize very quickly through a tiny hole under 7 psi. If you can detect it, you just put a patch over the hole and carry on.

Of course you DON'T want to in the path of a micrometiorite, after it has punched through the hull.

- what about virtual reality? Of course some mor developement is required but we are talking about an orbital equipment to be built in a near-by future of ten yerars but not this year or next year.

Hello, spacecowboy and WannabeSpaceCadet,

what do you think about the self-repairing hull being subject to another thread? It's menat for a vehicle but wouldn't it work at an assembly yard also - it would be an assembly yrad for vehicles to be launched from a space station (a part of an orbital spaceport in principle.

And I seem to remeber another way to hanlde micrometeorites also but do not know this moment what it was - may be something reacting elastically...

Our biggest problem is keeping the micrometeorite from passing through the drydock hull and "interfering with the work process", i.e. killing dock workers and damaging the ship. However, I can't think of any material off the top of my head that would prevent something moving at 34,000 miles per hour (twice orbital velocity, the closing speed seen when you are moving in the opposite direction from the object) from puncturing that hull. As far as self-repairing, that's great. But let's see what we can do to keep the little critters outside in the first place. And I don't know whether ice would make a good shield, but I do know it'd be pretty hard to keep it frozen in sunlight.

How about a kevlar sandwich with a foaming agent as the filling that solidifies on contact with air? This would seal on the inside of the dock and if you made the foam a contrasting colour to the kevlar punctures could easily be detected and patched over by an astronaut.

Make the whole thing out of triangle sections that can be attached to each other (possibly using slots along their edges) and you can make almost any shape you like. Dont graphic artists render pretty complex shapes in animation packages with triangles, if that is the case triangles should be flexible enough to create anything needed in space.

_________________A journey of a thousand miles begins with a single step.